In this Letter, we demonstrate ultraviolet(UV) spot position measurement based on the 4 H-SiC quadrant photodetectors(QPDs). The 4 H-SiC QPD with an 8 mm × 8 mm active area exhibits high uniformity across four qu...In this Letter, we demonstrate ultraviolet(UV) spot position measurement based on the 4 H-SiC quadrant photodetectors(QPDs). The 4 H-SiC QPD with an 8 mm × 8 mm active area exhibits high uniformity across four quadrants, with a consistent low dark current of ~18 p A and a responsivity of 0.111 A/W at 275 nm. Based on the QPD, the prototype system shows high positioning capability with a slight inherent nonlinearity. Correspondingly, the measurement error is analyzed and a calibration method utilizing the Boltzmann function is developed for the error correction. Evident improvement in positioning accuracy of the measurement system has been realized, achieving a position resolution of 0.3 μm and a mean positioning error of ~28.5 μm.展开更多
基金supported by the Innovation Program for Quantum Science and Technology (No.2021ZD0303400)the National Natural Science Foundation of China (Nos.61921005,U2141241,62374084,and U21A20496)the Key Research Program of Jiangsu Province (No.BE2023018)。
文摘In this Letter, we demonstrate ultraviolet(UV) spot position measurement based on the 4 H-SiC quadrant photodetectors(QPDs). The 4 H-SiC QPD with an 8 mm × 8 mm active area exhibits high uniformity across four quadrants, with a consistent low dark current of ~18 p A and a responsivity of 0.111 A/W at 275 nm. Based on the QPD, the prototype system shows high positioning capability with a slight inherent nonlinearity. Correspondingly, the measurement error is analyzed and a calibration method utilizing the Boltzmann function is developed for the error correction. Evident improvement in positioning accuracy of the measurement system has been realized, achieving a position resolution of 0.3 μm and a mean positioning error of ~28.5 μm.
